Breast Cancer Decline Linked to Hormone Therapy Decline

THURSDAY, Feb. 18 (HealthDay News) -- The rise and fall in U.S. breast cancer rates from 1992 to 2005 mainly reflects affluent white (non-Hispanic) women initially adopting then abandoning hormone replacement therapy (HRT) because of its breast cancer risk, according to a study published online Feb. 10 in the American Journal of Public Health.

Nancy Krieger, Ph.D., of the Harvard School of Public Health in Boston, and colleagues analyzed data from the Surveillance, Epidemiology and End Result (SEER) population-based cancer registries for the period 1992 to 2005 on 350,075 breast cancer cases. The researchers correlated socioeconomic status, race/ethnicity, age at diagnosis, and breast cancer tumor factors to the post-2002 decline in HRT that occurred in the wake of the Women's Health Initiative study pointing to increased breast cancer risk with the therapy.

The researchers found that the trend of breast cancer rising and then falling in the United States during the study period occurred only among white non-Hispanic women aged 50 years and older living in high-income counties, who had estrogen receptor-positive tumors. There were no similar trends among women who were black (non-Hispanic), Asian/Pacific Islanders, Hispanic, or American Indian/Alaska Natives.

"The recent decline in U.S. breast cancer incidence was not equally beneficial to all women, but instead mirrored the social patterning of hormone therapy use. Joint information on socioeconomic resources and race/ethnicity is vital for correctly understanding disease distribution, including that of breast cancer," the authors write.